When you say “government” in Libya, it’s never immediately apparent who you’re talking about. The group in charge of Tripoli is calling itself a government, but is mostly dominated by the Misrata city militia. The internationally recognized government, by contrast, has almost no territory, but a lot of troops from its merger with the self-proclaimed army of Gen. Khalifa Hifter.
For ISIS, it’s a distinction without a difference however, and the Libya affiliate of the jihadist faction is fighting both at the same time, along with some other smaller factions for good measure.
Forces loyal to the Tripoli government attacked ISIS in Sirte, trying to set up checkpoints around the power plant there. At least five of those “government forces” were killed in subsequent ISIS fighting.
That wasn’t keeping ISIS too busy, apparently, so they also launched a suicide attack against a post belonging to the army of the other Libyan government, east of Benghazi, and started a round of heavy fighting there, with death tolls yet to be released.
The parent ISIS organization has made its ability to fight on several fronts at once a defining feature, and the Libya affiliate, reportedly receiving ongoing advisory support from the parent and a huge influx of recruits, seems to be operating with the same goal in mind, keeping themselves engaged with multiple enemies at once, and enhancing their reputation as a force to be reckoned with.